Boeing has won a US$5.8 billion order for its 737 Max jets from China Aircraft Leasing Group Holdings Ltd, the lessor revealed in a statement to the Hong Kong stock exchange on Thursday.

China Aircraft’s Leasing’s order is for 50 single-aisle jets, which will be delivered through 2023, and is the company’s first purchase from Boeing.

The order bolsters already surging demand for the largest version of the 737 to date. The Max has become the fastest-selling plane in Boeing’s history.